The Victorian Overdose Deaths report, released on Thursday, found 4551 people died from drug overdoses between 2011 and 2020, while lab-made narcotics known as "New Psychoactive Substances" (NPS) contributed to 33 deaths last year.

RMIT drug researcher Dr Monica Barratt described the coronial report as sobering and said there had been "quite a rise" in NPS deaths.

"Every number is a life lost... it's greater than the road toll," she told AAP.

Dr Barratt said Victoria should lead the country by introducing drug sample testing, which would warn health services if new or stronger drugs were being sold.

She is developing a prototype drug alert for doctors and drug workers, to let them know when new drugs are circulating.

"It's very difficult to know how to deal with novel substances if you don't know they are there," she said.

NPS are designed to replicate the effects of other well-known illegal drugs such as cannabis, MDMA and cocaine, or pharmaceuticals such as benzodiazepines and opioids.

Some of the drugs are so new they have only been on the market for a matter of weeks or months, and there is some uncertainty about their impact in fatal overdose cases.

NPS use may have increased during the pandemic, the overdose report suggests, or the higher number of NPS-related deaths could be due to increased forensic detection.

"The data highlights the urgent need for appropriate harm reduction interventions to mitigate the risks associated with NPS use," the Coroner's Court report states.

Previous coronial inquests into deaths involving NPS have also called for the development of a drug early warning network and a drug checking service.

More broadly, pharmaceutical drugs such as benzodiazepines played a role in more than three quarters of fatal overdoses in 2020, while illegal drugs were involved in half of all cases, and alcohol was a factor in 30 per cent.

The anticonvulsant and anxiety drug Pregabalin has also emerged as a frequent contributor in deadly overdoses.

Men were twice as likely to die of an overdose than women, according to the report, with 35 to 54-year-olds most at risk.

The report did have some good news with a slight decline in overall deaths since 2018, while fears the pandemic might exacerbate drug harm have not been borne out in the figures so far.

Heroin deaths decreased by 12 per cent to 187 between 2019 and 2020 and fatal overdoses involving methadone fell also.

Since the controversial supervised injecting room trial in Richmond began in 2018, heroin deaths in the City of Yarra reduced from 26 to nine last year.

However, deaths from cocaine, MDMA and GHB overdoses all increased in 2020 to reach ten-year highs.

Australian Associated Press